Operating conditions different from PV systems on land
Efficient, long-term system operation depends on the optimal interaction of the installed components under the specific operating conditions, which can be very different from those on land. This applies not only to the PV modules themselves, transformers and junction boxes, but also to the cable solutions. Here, the Prysmian Group, world leader in the energy and telecom cable systems industry, has a portfolio of high-performance, durable copper cables to meet these requirements. It includes solutions both for interconnecting the various components of the floating PV system and for transporting the electricity generated on the water to the grid connection on land. Prysmian’s cable solutions are being used in one of Europe’s largest floating solar installations at Grafenwörth in Lower Austria, with a capacity of 24.5 MWp.
Material stress due to UV radiation, ozone, and constant movement
The cable range is optimally adapted to the special operating conditions. Since the cables are laid openly on the floating platform, this includes resistance to UV radiation as well as high temperatures and ozone levels, especially during long periods of sunshine. A high degree of flexibility is also required, which is particularly important due to the mechanical stress caused by the constant movement of the installation on the water. An important prerequisite for this is the use of copper as the material for the current conductors. This allows the cables to compensate for the constant movement without overheating and becoming damaged in the long term. The sheaths also meet the high ecological requirements for water protection.
Complete portfolio for all types of connection
Prysmian’s range of solar cables is centred around the “Tecsun” range, which is already used in many photovoltaic systems around the world. They are designed for free-moving, suspended or fixed installation in photovoltaic power generation systems with a rated voltage of up to 1.5 kV DC. They are the only solar cable system in the world to be certified according to DIN EN 50656-2 AD8, which means they can be permanently submerged in fresh water for their entire service life.
For the connection of the individual photovoltaic modules to the junction box via string lines, Prysmian also offers another tailor-made solution with its “Hydrofirm” cables. These copper cables, which are ideally suited for the loads in photovoltaic applications, have a drinking water-certified outer sheath. Among other things, they comply with the elastomer guidelines (ELL) of the German Federal Environment Agency (UBA) and the requirements of the Attestation de Conformité Sanitaire (ACS) in accordance with French law. The connection between the distributors and the transformers can be made with “Protolon M” cables, which are also suitable for high current flows with a high temperature resistance. A key challenge is to connect the floating PV system to the grid on land. Prysmian’s “Protolon ST” offer particular advantages here: they are highly flexible, specially designed for use in water and can be used in water depths of up to 500 metres.
The globally experienced cable specialist thus offers a portfolio of suitable cable solutions that are optimally matched to larger floating photovoltaic systems and have already proven themselves in many applications. Prysmian will be presenting it at InterSolar Europe in Munich, Germany from 14 to 16 June (Hall A4, Stand 559).
Further information on “Tecsun” at https://www.prysmiangroup.com/en/tecsun, on the entire range at https://de-catalogue.prysmiangroup.com/s/?language=en_GB
